(1) Field of the Invention
This invention relates to an isolator for isolating stepper motor vibration from a frame in which the motor is mounted.
(2) Background Information
Stepper motors are used in association with printing and with paper forms handling where a high degree of positional accuracy is required. Stepper motors operate by rotating or "stepping" in very small increments while under the control of associated electronics. One of the problems with stepper motors is that they are generally noisy in operation.
Another problem with stepper motors is that they are designed to be located in a mounting frame by a very short circular step appearing on the face of each motor. This circular step is about 1 1/2 inches in diameter, with the step being about 0.062 inch in height for one such stepper motor. When one attempts to put isolator material between the circular step on the mounting face and the mounting frame, there is little left of the circular step to provide the mounting function performed by the circular step relative to the mounting frame.
One prior art way of solving the problem mentioned in the previous paragraph, is to machine away a portion of the motor face to provide a step of increased height to accommodate the isolation member and still provide enough of a step to perform the locating functioned mentioned. This method results in a motor which is more expensive than a standard motor.
An object of this invention is to obviate the problem mentioned in the previous paragraph.
Another object is to provide an apparatus which provides vibration isolation for the stepper motor relative to the mounting frame, with the apparatus being a low cost one.
In a preferred embodiment of this invention, there is provided an apparatus comprising:
a stepper motor having a mounting flange, a mounting face, and a circular locating step located on said mounting face, with said circular locating step having a first dimension; PA1 a first member mounted on said circular step and shaped to provide a first dimension greater than the first dimension of said circular locating step; PA1 a frame having a mounting hole therein; PA1 an isolation member mounted on said first member and shaped to isolate said first member and said mounting flange from said frame; and PA1 said frame having retaining means thereon retaining said mounting flange thereto with said isolation member positioned therebetween.
The above objects and advantages of this invention will be more readily understood in relation to the following description, claims and drawing.